$msg.get not working when passed into tool class - upgrade Tools 1.1 to 1.4

I'm upgrading from Velocity 1.4 to 17, Vel Tools from 1.1 to 1.4, Struts 1.24 to 1.3.10
I have a button tool which takes the following params:

$button.render( "", $msg.get('login.form.submit'), "button", "function();loginForm.submit();" )
The render method bulids a string buffer and calls get(key)
Was working before upgrade

Now, the button class is valid but does not parse $msg.get(key)
As a matter of fact, based on my logs, the render method is not even getting called.

However, if I do this:
$button.render( "stopDebugging", "Stop Debugging", "button", "stopStart('stop')" )
The render method is called but there's an exception bc get(key) expects Ljava.lang.String as opposed to java.lang.String